AuthorTopic: jack audio and ardour (Read 3447 times)

I followed the steps on Headacher's web site to get Jack/Ardour working on Vector Linux 5.8 for the testing packages of jack and ardour on Vector Linux 5.9 Standard.

Has anyone done this with success ? It seems I'm getting stutters in my recordings. I also notice it during playback - if I start moving my mouse a lot or open any other apps during playback in Ardour I get more stutters...This is what I did:chgrp audio /usr/bin/jackdadding an extra line to /etc/rc.d/rc.local - modprobe realtime gid=17

Any thoughts on why this is happening. I've really been enjoying Vector - I switched from Fedora 7, hoping to have a leaner and meaner system - which I have for most intensive purposes. I'll be quite sad if I can't get the audio working though as that was quite easy in Fedora due to the PlanetCCRMA at home ports... I only got the stuttering happenig in fedora when I tried to use to many plugins...

I have to admit I've only tried Ardour for a few minutes. I haven't followed my own HOWTO for a while, perhaps I should do it some time and look for errors / things that may be unclear.

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It seems I'm getting stutters in my recordings. I also notice it during playback - if I start moving my mouse a lot or open any other apps during playback in Ardour I get more stutters...

How do you start jackd? Are you sure it´s running with realtime priority? Do you get a lot of xruns (I think you do). If you use qjackctl (give it a try if you haven't, it's well worth it) you can try increasing the buffers/period setting. If not, you should be able to start jack from command line like this (where 4 is the number of buffers/period)

hey - thx for the reply - i'm reluctant to believe i could be this much of a cracksmoker, but its possible that i didn't click play in qjackctl... I tried jack from cmdline as you suggested and i recorded with no prob... I upped the buffers to 4 in qjackctl and all seems to be rockin. I am a very happy camper - thx headacher - you are my hero.

for some reason, i cannot start jack with -R, it produces an error, starting without the realtime option works fine though.

some other questions: sometimes i edit a project in ardour and suddenly the main sound (big play button) stops to work (the track is still transported, but i can hear no sound). however, just selecting the single files (ctrl+rightmousebutton, play) works. any hints?

and i cannot have xmms and ardour playing a sound when both are opened. is this normal behaviour? why do they block each other, as they both rely on alsa (not oss)?

If you want some serious realtime capabilities I highly recommend a 2.6.24.x kernel patched with molnar's realtime preemption patch. (You'll either need a little known program called set_rlimits or be good with PAM to get it to work for non-root users, realtime-lsm won't work.) with it I can get 2.9 ms latency with an older budget laptop and a usb soundcard. it's sweet.

some other questions: sometimes i edit a project in ardour and suddenly the main sound (big play button) stops to work (the track is still transported, but i can hear no sound). however, just selecting the single files (ctrl+rightmousebutton, play) works. any hints?